My 2001 Honda civic ex the P0135 code show on the car scan and Check engine light is always on

Question

What could be the problem my car is always over heating

Answer 1

P0135  02 sensor heater circuit malfunction Bank 1 Sensor 1

If the engine is over heating the overheating condition has to be resolved first, this would be the best course of action to take, P0135 is mostly straight forward it is the heater element of a 02 sensor that degrades after so many miles of service